Vibratory apparatus for atomizing liquids



Oct. 29, 1963 w. L. DRAYER ETAL 3,108,749

VIBRATORY APPARATUS FOR ATOMIZING LIQUIDS 2 Sheets-Sheet 1 Filed March28, 1962 PRESSUR/ZZ'D INVENTORS (MY/1km L? 2;?)1 616 caaa BY fi z%ATTORNEY PPESSUR/ZED All? Oct. 29, 1963 w. L- DRAYER ETAL VIBRATORYAPPARATUS FOR ATOMIZING LIQUIDS 2 Sheets-Sheet 2 Filed March 28, 1962BESSU/F/ZED FL U/D TNVENTORS FLU/0 A RNEY United States Patent 3,108,749VIBRATURY APPARATUS FUR ATOMIZING LIQUIDS William L. Drayer, Warren, andSolo A. Mahala, Royal Oak, Mich, assignors to General MotorsCorporation, Detroit, Mich, a corporation of Delaware Filed Mar. 28,1962, Ser. No. 183,218 9 Claims. (Cl. 239l02-) This invention relates toa vibration generator and more particularly to a vibrator apparatus andmethod having particular utility for atomizing liquid.

It is well known that a liquid can be atomized by causing it to contacta vibrating reed or similar member such that the vibratory mechanicalenergy breaks up the liquid and disperses it as small droplets. However,liquid atomizers of this type have had only limited utility, for onereason because they have heretofore incorporated relatively complex ordelicate structures expensive to manufacture and difficult to maintain.Also, there has been the ditficulty of adequately controlling the sizeand dispersion pattern of the droplets produced along with that ofaccomplishing high eflieiency in the utilization of the vibratory energyfor the desired atomization and dis spersion of the liquid. Hence,vibratory type atomizers have not enjoyed the popularity and wide fieldof application as in the case of other types of atomizers, for example,the air spray gun or the electrostatic type atomizer.

It is an object of this invention to provide an improved, highlyefiicient and durable vibration generator having particular utility as aliquid atomizer.

Another object is the provision of an improved method for atomizing aliquid by the utilization of vibrating energy.

Another object is the provision of an improved vibration generator ofthe type wherein a mass is driven at high speed in an orbital path bymeans of fluid pressure.

A further object is to provide a liquid atomizing apparatusincorporating a mass which is fluid driven in an orbital path so as togyrate the free end of a liquid carrying conduit at a speed suflicientto atomize the fluid passing through the conduit.

A still further object of this invention is to provide an apparatus inwhich a standing gyratory wave is propagated in a tube whereby the freeend of the tube is gyrated at a speed sufiicient to atomize a liquidpassing through the tube.

Another object of the present invention is to provide an apparatushaving an elongated tube in which a standing gyratory wave is propagatedand the end of the tube is located at the antinode so that sufficientcentrifugal force is created to atomize the fluid passing through thetube.

Briefly, the vibration generator of this invention includes an outerconfining housing or sleeve member and a generally cylindrical masswithin the housing arranged for orbital movement therein. The mass isconnected to a shaft that is supported at a point spaced from the masssuch that rotation of the shaft about its longitudinal axis is precludedwhile the free end of the shaft adjacent the mass is free to rgyrate byreason of bending and pivotal motion of the shaft about its point ofrigid support. Means are provided for directing compressed air or otherfluid to the mass so as to drive it in an orbital path within theconfines of the housing thereby causing the shaft to gyrate and set upvibrations in the housing. Further, in accordance with the invention,the mass is suspended by the connecting shaft so there is substantiallyno contact between the outer surface of the mass and the inner surfaceof the outer housing during its orbital movement; the mass beingeccentrically located within the housing so as to create high and lowpressure support areas while the pressurized air or other fluid isapplied. In effect then, the mass is of the 3 ,18,749 Patented Oct. 29,1963 ice nature of a floating bearing which has deliberately been madeunstable such that the stream of fluid produces circular translation ororbital movement of the mass within the housing, however without anysubstantial contact between the two.

It has been found that if the shaft is formed as a tube with the freeend thereof extending beyond the mass in a cantilever form, the orbitalmovement of the mass results in a similar orbital or gyrato-ry movementat the end of the tube. The mass can be orbited at a frequency whichsets up a standing gyratory wave in the tube, and by locating the freeend of the tube at an antinode and causing it to gyrate at a highfrequency, a centrifugal force can be produced which is of a magnitudefully adequate to atomize and disperse a liquid passed through the tube.

Other objects and features of the invention will be ap parent from thefollowing detailed description made with reference to the accompanyingdrawings in which:

FIGURE 1 is an end view of the subject vibration generator constructedin accordance with the invention;

FIGURE 2 is a sectional View taken on lines 22 of FIGURE 1;

FIGURE 3 is a modification of the vibration generator shown in FIGURES 1and 2;

FIGURE 4 is a sectional view taken on lines 4-4 of FIGURE 3.

FIGURE 5 shows the subject vibration generator modified for atomizing afluid;

FIGURE 6 shows the atomizer of FIGURE 5 with an extending liquid conduithaving a standing gyratory wave propagated therein;

FIGURE 7 is an enlarged view taken on lines 7-7 of FIGURE 6;

FIGURE 8 shows the apparatus of FIGURE 5 with an extending liquidconduit being bodily gyrated.

Referring now to the drawings, FIGURES 1 and 2 illustrate one embodimentof the subject vibration generator comprising an elongated sleeve shapedhousing 12 terminating with a free end 14 while the other end isappropriately connected to a support 16. Within the housing 12, acylindrical mass or translator 18 is integrally connected with a tubularshaft 20 having an air or other fluid passage 21 formed therein; theportion of the shaft adjacent the support 16 being rigidly secured by asupport member 22, which as shown, is a separate memher from the tubeand housing. The support member 22 can be made integral with the housing12 or tube if desired, the only requirement being that a suitable bondexist between the members to form a rigid connection so as to preventrotative movement of the tube 20 about its longitudinal :axis. Thegenerator, as shown, is made of a metallic material, however, it can bemade from a tough plastic material such as nylon; the choice of materialbeing dictated by the intended use for the generator.

The mass 18 includes a plurality of ciroumfe-rentially spaced ports 24that project tangentially from a passage 25 centrally formed in themass. Each of the ports 214- oonnect with a restricted passage ororifice 2 6 that opens at the peripheral surface of the mass fordirecting a high velocity flow of fluid against the inner surface of thehousing 12. The center passage 25 formed in the mass communicates withthe tube opening 21 which in turn is connected to a source ofpressurized fluid 34 for purposes which will hereinafter be explained.

The tube 20' is mounted by the suport portion 22 in a manner thatpermits the cylindrical mass to be eccentrically disposed within theinner portion of the housing 12. This is shown in FIGURE 1 with a largerair space or region 28 existing at one side of the mass than at theregion 30 located diametrically opposite the, region 28.

This eccentric arrangement of the mass can be accomp lished by eithersupporting the tube 26* on an axis ina clined to the center axis of thehousing, or 'by supporting the tube at a point so removed from the mass18, that the weight of the mass displaces the latter eccentrically withrespect to the housing passage 13. The latter arrangement would be usedmost effectively when the generator is mounted in a horizontal plane asshown in FIG- URE 2.

FIGURES 3 and 4 show a modification of the vibration generator shown inFIGURES 1 and 2, and in this instance, a solid shaft 36 is made integralwith a solid cylindrical mass 38 with an outer housing 40 terminating atone end with a wall 42 having an aperture 44 centrally formed thereinthat serves as an air exhaust passage. A cylindrical liner or sleeve 46is fixedly secured within the housing 40 and includes a plurality ofcircumferentially spaced ports 48, each of which connect with an orifice49, as best viewed in FIGURE 3. The axis of each port and orifice isoffset with respect to the center of the housing so as to provide astream of fluid at a tangential attitude against the peripheral surfaceof the mass 38. An annular passage 50 formed in the outer surface of thesleeve 46 connects the several ports with a pressurized fluid that isdirected to the housing 40 from a source 51 via a conduit 52. As in thegenerator shown in FIG- URES 1 and 2, the shaft 36 is rigidly supportedat a point removed from the mass by a support 54 that disposes the masseccentrically within the housing, and precludes rotative movement of theshaft 36 about its longitudinal axis.

In operating the vibration generator shown in FIG- URES 1 and 2,pressurized fluid is directed through the tube 24) to the center passage25 formed in the mass 18, whereupon the fluid then exits from the massvia the ports 24 and orifices 26 as a high velocity stream tangentiallydirected against the inner wall of the housing 12. Due to the eccentricdisposition of the mass 18 in the housing, the area into which the fluiddispenses varies at points around the mass resulting in a high or lowvelocity fluid stream with an accompanying low or high pressure region.This can be understood best by considering the fluid flow in two regionswhen the mass is located as shown in FIG- URE 1. In the region 30, a lowvelocity-high pressure space exists because of the small air spacelocated between the outer surface of the mass and the adjacent surfaceof the housing with the result of an increased restriction on the flowof the fluid from the adjacent orifice. other hand, the airspace in theregion 28 is larger than that in region 30 thereby providing a lesserflow restriction on the fluid resulting in a high velocity fluid-flow.Because of the high and low pressure regions and the tangential attitudeof the outlet ports 24, the mass 18 moves in an orbital pattern towardthe regions of lower pressure under the influence of the higher pressureregions. Likewise due to the movement of the mass, the pressure regionsadjacent the several orifices continuously vary in value resulting inthe mass being pushed from a high pressure region to a low pressureregion and thereby creating new regions of low and high pressure. Themovement of the mass 18 causes the tube 26 to bend elastically, anddirect a rotating force impulse through the support 22 to the housing1-2, causing a vibration of the housing at a frequency corresponding tothat of the orbiting mass.

It should be noted that during the orbital movement of the mass, a layerof air continuously exists between the outer surface of the mass and theinner surface of the housing with the result that there is substantiallyno contact between the mass and housing as the former follows an orbitalpath. The pressurized fluid serves the dual function of driving the massand also supplies a fluid cushion or support that precludes surfacecontact between the members. This is an unique feature of thisgenerator, and it can be readily appreciated that with this arrangementthe life of the vibration generator is immeasurably increased due to theelimination of any wear problem.

The operation of the generator shown in FIGURES 3 and 4 is similar tothat of the generator shown in FIG- On the 4 URES 1 and 2, except thatin this embodiment the fluid is being directed onto the mass 38 from theorifices 49 formed in the sleeve 46. Here again, the mass 38 is disposedeccentrically within the housing so that low and high pressure regionsexist around the outer surface of the mass causing an orbital movementof the mass during the fluid flow with resulting vibrations beingdirected to the housing 44 as described above.

Referring now to FIGURES 5 through 8, a generator is shown with a tube56 rigidly connected to a mass 58 and extending beyond the housing 6-2to form a tube extension 64 terminating with a nozzle 68. The tubecommunicates with a source of liquid 4% that supplies liquid to thenozzle at a controlled rate by a conventional metering unit 67. The tube56 is fixed in the housing by a support '70 that eccentrically disposesthe mass 58 in the housing in a manner similar to the aforementionedgenerators. A passage 72 is provided in the body of the housing 62 forexhausting the fluid emanating from the ports 74 which receivepressurized fluid from a source 76 via the conduit 78 in a mannersimilar to that described with regard to the generator shown in FIGURE 3and 4.

At this time it should be noted that the length of the tube ispredicated upon the operating frequency of the generator. Bydimensioning the tube so that the natural frequency of the latter isequal to the operating frequency of the generator, a standing wave ispropagated in the tube, as shown in FIGURE 6, that results in increaseddeflection of the nozzle 68. This in turn, results in increasedcentrifugal forces of a magnitude capable of atomizing the liquid into afine mist or spray at the nozzle 68. Acceptable atomization can also beobtained if the tube extension 64 is shortened so as to have a naturalfrequency greater than the operating frequency of the generator with theresult that the extension is bodily gyrated to produce an orbitalmovement of the nozzle 68 as shown in FIGURES 7 and 8. For mostefiicient operation, the vibration generator should be operated abovecycles per second, and as aforementioned, in the resonant frequencyrange of the tube.

During the operation of the atomizer, a pressurized fluid enters thegenerator through the passage 7 S, and exits from the ports 74 as a highvelocity stream directed against the outer surface of the mass 58. Theeccentric disposition of the mass 58, causes the mass to orbit withinthe cylindrical housing 40 with similar movement being transmitted tothe attached tube 56, as aforementioned. Depending upon the length ofthe tube and the frequency at which the mass 58 is orbiting, either astanding gyrating wave or a bodily movement is propagated in the tubeduring which time liquid is directed through the tube 56 at a controlledrate, and as it reaches the nozzle 68, the centrifugal forces created bythe orbiting tube serves to break up the liquid into fine particles andproject them into the surrounding atmosphere.

Various changes and modifications can be made in my apparatus withoutdeparting from the spirit of the invention. modifications arecontemplated and therefore we do not wish to be limited in any mannerexcept as defined by the appended claims.

What is claimed is:

1. An apparatus for atomizing liquid comprising, a

housing, a tube extending through said housing and having a free end,means for supplying liquid to the free end of said tube, an enlargedmass rigidly connected with said tube for orbital movement in saidhousing, said mass being located in said housing at a point spaced fromsaid free end, and means for driving said mass in said orbital path at afrequency at least equal to the resonant frequency of the tube whereby astanding gyr'atory wave is created in the body of the tube and liquid iscentrifugally atomized at the free end of the conduit.

2. An apparatus for atomizing liquid, comprising a cylindrical housing,a tube extending through said hous- It should be understood that thesechanges and ing and having a free end, means for supplying liquid to thefree end of said tube, an enlarged mass rigidly connected with said tubefor orbital movement in said housing, and fluid passages in said housingtangentially located around said mass and adapted to direct a fluidstream against said mass to drive the latter in an orbital path at aspeed suflicient to create a gyratory standing Wave in the tube andcause said liquid to be atomized at the free end of the tube.

3. In an apparatus for generating vibrations, a housing having anopening therein, an enlarged mass having an attached shaft disposed insaid opening, said mass being located in said opening, a portion of saidshaft fixed in said housing with said mass located off-center withrespect to said opening, and fluid means for directing a stream of fluidagainst the mass for driving said mass in an orbital path in closeproximity to the housing so as to cause a rotating force impulse to beapplied to said portion of said shaft.

4. In an apparatus for generating vibrations, a housing having acircular opening therein, an enlarged circular mass disposed in saidopening and having a shaft attached thereto, said mass being located insaid opening, a portion of said shaft fixed in said housing so as toprevent rotation about the shaft axis, said circular mass locatedolfcenter with respect to said opening, means for supplying pressurizedfluid to said housing, and ports in said housing adjacent said mass fortangentially directing said pressurized fluid against said mass wherebysaid means is driven in an orbital path in close proximity to thehousing whereby a rotating force impulse is applied to said portion ofthe shaft.

5. In apparatus for generating vibrations, a housing having a circularopening therein, an enlarged circular mass disposed in said opening andhaving a shaft attached thereto, said mass being located in said openingat one end of said shaft, a portion of said shaft fixed in said housingso as to prevent rotation about the shaft axis, said circular masslocated off-center with respect to said opening, means for supplyingpressurized fluid to said mass, and ports in said mass for tangentiallydirecting said pressurized fluid against said housing whereby the massis driven in an orbital path in close proximity to the housing whereby arotating force impulse is applied to said portion of the shaft.

6. In an apparatus for generating a rotating force impulse, a housinghaving a circular opening therein, a

cylindrical mass disposed in said opening and having a diameter greaterthan one-half the diameter of the opening, a shaft connected to thecenter of the mass and having a portion thereof fixed in the housing soas to prevent rotation about the shaft axis, a pressurized fluid passageformed in the shaft, a plurality of fluid orifices formed in the massand located therein so as to direct fluid tangentially against thehousing, means for com necting said fluid passage to said orifices, anda source of pressurized fluid for directing fluid through the passage tothe orifice whereby a high velocity stream of fluid impinges against thehousing and causes an orbital movement of the mass in close proximity tothe housing. 7. An apparatus for atomizing liquid, comprising a sourceof pressurized fluid, a source of liquid, an elongated cylindricalhousing having an elongated circular opening formed therein, anelongated tube located in said opening and connected to the liquidsource, one end of said tube fixed in the housing and the other endextending beyond the housing, a cylindrical mass centrally fixed to saidtube and eccentrically locatedwithin the housing opening, a plurality oforifices formed in the housing, said orifices circumferentially spacedaround said mass and adapted to direct a stream of pressurized fluidtangentially against the mass, means for connecting said source ofpressurized fluid to the orifices, means for controlling the rate ofliquid flow from the liquid source to the other end of the liquid tube,a passage formed in the housing for exhausting pressurized fluidtherefrom, said pressurized fluid emanating from the orifices beingadapted to drive the mass in an orbital path in close proximity to thehousing and cause a gyratory movement of the other end of the tube at aspeed sufficient to centrifugally atomize the liquid. I

8. The apparatus of claim 7 wherein said pressurized fluid drives saidmass at a frequency above cycles per second in the resonant frequencyrange'of the tube.

9. An apparatus for atomizing liquid comprising, a housing, a tubehaving a portion rigidly secured in said housing and having a free endextending beyond said housing, means for supplying liquid to said freeend at a controlled rate, an enlarged mass rigidly connected to saidtube at a point intermediate the free end and fixed portion of the tube,said mass being located in said housing, and means including a pluralityof passages in said housing for driving said mass in an orbital path ata frequency not less than the resonant frequency of said tube to causesaid liquid to be atomized at said free end.

References Cited in the file of this patent UNITED STATES PATENTS2,752,195 Whitehead June 26, 1956 2,854,283 Hruby Sept. 30, 19583,030,028 Hruby Apr. 17, 1962 3,034,728 Hruby May 15, 1962

1. AN APPARATUS FOR ATOMIZING LIQUID COMPRISING, A HOUSING, A TUBEEXTENDING THROUGH SAID HOUSING AND HAVING A FREE END, MEANS FORSUPPLYING LIQUID TO THE FREE END OF SAID TUBE AN ENLARGED MASS RIGIDLYCONNECTED WITH SAID TUBE FOR ORBITAL MOVEMENT IN SAID HOUSING, SAID MASSBEING LOCATED IN SAID HOUSING AT A POINT SPACED FROM SAID FREE END, ANDMEANS FOR DRIVING SAID MASS IN SAID ORBITAL PATH AT A FREQUENCY AT LEASTEQUAL TO THE RESONANT FREQUENCY OF THE TUBE WHEREBY A STANDING GYRATORYWAVE IS CREATED IN THE BODY OF THE TUBE AND LIQUID IS CENTRIFUGALLYATOMIZED AT THE FREE END OF THE CONDUIT.